KR20210048160A - Electric brake system and control method thereof - Google Patents

Abstract

According to one embodiment, an electric brake system having a hydraulic circuit supplying hydraulic pressure to a wheel cylinder comprises: a plurality of electric valves provided to open and close a flow passage of the hydraulic circuit; and a control unit correcting target current of the operating electric valve among the electric valves based on voltage inputted from a battery of a vehicle during braking control and increasing current supplied to the electric valve to enable the current of the operating electric valve to reach the corrected target current.

Description

Electronic brake system and its control method {ELECTRIC BRAKE SYSTEM AND CONTROL METHOD THEREOF}

The disclosed invention relates to an electronic brake system and a control method thereof, and more particularly, to an electronic brake system for generating a braking force according to an electric signal corresponding to a displacement of a brake pedal, and a control method thereof.

In general, the electronic brake system receives the driver's braking intention as an electrical signal from a pedal displacement sensor that senses the displacement of the brake pedal when the driver depresses the brake pedal, and operates a hydraulic pressure supply device based on this, so that the hydraulic pressure required for braking is transferred to the wheel. It is supplied to the cylinder.

The electronic brake system generates hydraulic pressure required for braking by changing the position of the hydraulic piston by the rotational force of the motor, and brakes the wheel by introducing the generated hydraulic pressure into the wheel cylinder. For example, the electronic brake system is divided into a simulator unit that forms pedal effort according to the driver’s braking will, and a circuit unit that transmits the hydraulic pressure generated by the motor to the wheel cylinder, and an electromagnetic valve responsible for each function. Can include.

Due to the characteristics of such an electronic brake system, the operation of the solenoid valve is limited according to a voltage applied to the system from a battery provided in the vehicle.

If the voltage of the battery provided in the vehicle drops momentarily during the operation of the electronic brake system, the solenoid valve in operation may not be kept on and may be turned off. For this reason, it is difficult to ensure the operation stability of the solenoid valve, and the pressurization, maintenance, or depressurization performance may be deteriorated.

Japanese Unexamined Patent Publication No. Hei 7-17375 (published on January 20, 1995)

An aspect of the disclosed invention is to provide an electronic brake system capable of stably securing braking performance by ensuring the operation stability of an solenoid valve even when the system voltage fluctuates, and a control method thereof.

An aspect of the disclosed invention is an electronic brake system having a hydraulic circuit for supplying hydraulic pressure to a wheel cylinder, comprising: a plurality of solenoid valves provided to open and close a flow path of the hydraulic circuit; And correcting a target current of an operating solenoid valve among the plurality of solenoid valves based on a voltage input from a battery of the vehicle during braking control, and allowing the current of the operating solenoid valve to reach the corrected target current. An electronic brake system including a control unit for increasing the current supplied to the valve may be provided.

The control unit may correct a target current of the operated solenoid valve when the instantaneous voltage of the battery drops.

The control unit may increase the target current of the solenoid valve in operation to a max current that guarantees operability within a pressure band guaranteed by the solenoid valve in operation.

The control unit may increase the current of the solenoid valve in operation to the max current, and when the max current is reached, the control unit can reduce the hold current for maintaining the on state of the solenoid valve in operation after maintaining for a preset time. have.

When a voltage input from the battery is lower than a preset voltage, the controller may increase a target current of an operating solenoid valve among the plurality of solenoid valves.

It may include a voltage sensor for sensing the voltage input from the battery.

Another aspect of the disclosed invention is a control method of an electronic brake system having a hydraulic circuit for supplying hydraulic pressure to a wheel cylinder, detecting a voltage input from a battery of a vehicle during braking control, and detecting the hydraulic pressure based on the sensed voltage. An electromagnetic brake that corrects a target current of an operating solenoid valve among a plurality of solenoid valves that open and close a flow path of a circuit, and increases the current of the operating solenoid valve so that the current of the operating solenoid valve reaches the corrected target current A method of controlling the system may be provided.

The target current correction may increase a target current of an operating solenoid valve among the plurality of solenoid valves when a voltage input from the battery is lower than a preset voltage.

The increase in current of the solenoid valve in operation may increase the target current of the solenoid valve in operation to a maximum current that guarantees operability within a pressure band guaranteed by the solenoid valve in operation.

When the current of the solenoid valve in operation reaches the max current, the current of the solenoid valve in operation may be maintained for a predetermined period of time, and then a hold current for maintaining the on state of the solenoid valve in operation may be reduced.

According to an aspect of the disclosed invention, even if the battery voltage of the vehicle drops momentarily, the operation stability of the solenoid valve in operation can be ensured, thereby stably securing braking performance.

1 shows a hydraulic circuit diagram of an electronic brake system according to an embodiment.
2 shows a control block of an electronic brake system according to an embodiment.
3 shows a target current pattern of the solenoid valve in the electronic brake system according to an embodiment.
4 is a diagram illustrating a change of a target current of the solenoid valve upon an instantaneous voltage drop during braking control of the electronic brake system according to an exemplary embodiment.
5 is a diagram illustrating a change of a target current of the solenoid valve from a hold current to a max current and then back to a hold current when an instantaneous voltage drops during braking control of the electronic brake system according to an embodiment.
6 shows a control flow of an electronic brake system according to an embodiment.

The same reference numerals refer to the same elements throughout the specification. This specification does not describe all elements of the embodiments, and general content in the technical field to which the disclosed invention belongs or content overlapping between the embodiments will be omitted. The term'unit, module, member, block' used in the specification may be implemented in software or hardware, and according to embodiments, a plurality of'units, modules, members, blocks' may be implemented as one component, It is also possible for one'unit, module, member, block' to include a plurality of components.

Throughout the specification, when a part is said to be “connected” with another part, this includes not only the case of direct connection but also the case of indirect connection, and the indirect connection includes connection through a wireless communication network. do.

In addition, when a part “includes” a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

Throughout the specification, when a member is positioned “on” another member, this includes not only the case where a member is in contact with another member, but also the case where another member exists between the two members.

Terms such as first and second are used to distinguish one component from other components, and the component is not limited by the above-described terms. Singular expressions include plural expressions, unless the context clearly makes exceptions.

In each step, the identification code is used for convenience of explanation, and the identification code does not describe the order of each step, and each step may be performed differently from the specified order unless a specific order is clearly stated in the context. have.

1 shows a hydraulic circuit diagram of an electronic brake system according to an embodiment.

Referring to FIG. 1, the electronic brake system stores the pressurized medium by being coupled to the upper side of the master cylinder 20 and the master cylinder 20 that pressurizes and discharges the pressurized medium contained therein by the operation of the brake pedal 10. The reservoir 30 to perform, a wheel cylinder 40 provided in each of the wheels RR, RL, FR, FL, a simulation device 100 that provides a reaction force according to the foot force of the brake pedal 10, and a brake pedal ( A hydraulic pressure supply device 200 that generates hydraulic pressure by driving by an electrical signal corresponding to the displacement of 10) and supplies the generated hydraulic pressure to each wheel cylinder 40 provided in each wheel (RR, RL, FR, FL), and , It may include a hydraulic control device 300 for controlling the flow of the hydraulic pressure delivered to each wheel cylinder 40 by the hydraulic pressure supply device 200.

The simulation device 100 may include a pedal simulator 110 and a simulator valve 120. The pedal simulator 110 includes a simulation chamber 111 provided to store a pressurized medium flowing out of the master cylinder 20, a reaction piston 112 provided in the simulation chamber 111, and a reaction spring 113 that elastically supports it. ) Can be included. The simulator device 100 may create a pressure in the simulation chamber 111 to provide an appropriate pedal feel to the driver.

The simulator valve 120 may be a normal closed type solenoid valve that is normally closed and operates to open the valve upon receiving a driving signal from the control unit (ECU) 500.

The hydraulic pressure supply device 200 may be provided to generate the hydraulic pressure of the pressurized medium through mechanical operation by receiving the driver's braking intention as an electrical signal from the pedal displacement sensor 11 that senses the displacement of the brake pedal 10. have.

The hydraulic pressure supply device 200 includes a hydraulic pressure supply unit 210 that provides a pressurized medium pressure delivered to each wheel cylinder 40, and a motor-driven actuator that operates the hydraulic pressure supply unit 210 using a motor 221 ( 220) and a plurality of control valves 230 for controlling the flow of hydraulic pressure.

The hydraulic pressure providing unit 210 uses a cylinder block 211 to accommodate a pressurized medium, a hydraulic piston 214 accommodated in the cylinder block 211, and the power output from the motor driving actuator 220 to a hydraulic piston. It may include a drive shaft 215 transmitted to (214). The cylinder block 211 may include a first pressure chamber 212 positioned in front of the hydraulic piston 214 and a second pressure chamber 213 positioned behind the hydraulic piston 214.

The plurality of control valves 230 may include first to fourth control valves 231, 232, 233 and 234.

The first to third control valves 231, 232, 233 are hydraulic control devices 300 from the first pressure chamber 212 and/or the second pressure chamber 213 by a combination of flow paths according to the opening and closing of the valves. ), or the flow of the pressurized medium transmitted between the first pressure chamber 212 and the second pressure chamber 213 may be controlled. For example, the first to third control valves 231, 232, and 233 are normally closed, but a normally closed type solenoid valve that operates to open the valve upon receiving a driving signal from the controller 500. Can be

The fourth control valve 234 may control the flow of the pressurized medium between the second pressure chamber 213 and the reservoir 30. For example, the fourth control valve 234 may be a normally open type solenoid valve that is open in a normal state and operates to close the valve upon receiving a driving signal from the control unit 500.

The plurality of control valves 230 may have different valve numbers and/or valve types depending on the flow path structure.

The hydraulic pressure supply device 200 may include a motor pump or a high pressure accumulator instead of the hydraulic pressure providing unit 210 and the motor driving actuator 220.

The hydraulic control device 300 includes a first hydraulic circuit 310 for controlling the flow of hydraulic pressure delivered to the first and second wheel cylinders 41 and 42 among the four wheel cylinders, and the third and fourth wheel cylinders. It may include a second hydraulic circuit 320 for controlling the flow of the hydraulic pressure delivered to (43, 44).

For example, the first hydraulic circuit 310 may control braking force of the right front wheel FR and the left rear wheel RL. The second hydraulic circuit 320 may control braking force of the right rear wheel RR and the left front wheel FL.

The first hydraulic circuit 310 includes first and second inlet valves 311 and 312 to control the flow and hydraulic pressure of the pressurized medium transmitted from the hydraulic pressure supply device 200 to the first and second wheel cylinders 41 and 42. ) Can be included.

The first hydraulic circuit 310 may include first and second outlet valves 313 and 314 to control the flow of the pressurized medium discharged from the first and second wheel cylinders 41 and 42.

The second hydraulic circuit 320 includes third and fourth inlet valves 321 and 322 to control the flow and hydraulic pressure of the pressurized medium transmitted from the hydraulic pressure supply device 200 to the third and fourth wheel cylinders 43 and 44. ) Can be included.

The second hydraulic circuit 320 may include third and fourth outlet valves 323 and 324 to control the flow of the pressurized medium discharged from the third and fourth wheel cylinders 40.

The first to fourth inlet valves 311, 312, 321, and 322 may be normally open type solenoid valves that are open in a normal state and operate to close when a driving signal from the controller 500 is received.

The first to fourth outlet valves 313, 314, 323, and 324 may be normally closed type solenoid valves that are normally closed and operate to open the valve upon receiving a driving signal from the control unit 500.

In addition, the electronic brake system may include a cut valve 400 provided in a backup passage connecting the master cylinder 20 and the hydraulic control device 300.

For example, the cut valve 400 may include a first cut valve 410 and a second cut valve 420.

The first cut valve 410 may be provided on a first backup passage connecting the master cylinder 20 and the first hydraulic circuit 310.

The second cut valve 420 may be provided on a second backup passage connecting the second hydraulic circuit 320 of the master cylinder 20.

The first cut valve 410 and the second cut valve 420 may be normally open type solenoid valves that are open in a normal state and operate to close the valve upon receiving a driving signal from the controller 500.

When the first and second cut valves 410 and 420 are closed, the hydraulic pressure provided from the hydraulic pressure supply device 200 can be supplied to each wheel cylinder 40 through the first and second hydraulic circuits 310 and 320. have. When the first and second cut valves 410 and 420 are opened, hydraulic pressure provided from the master cylinder 20 may be supplied to each wheel cylinder 40.

In addition, the electronic brake system may include a control unit (ECU) 500 that performs overall control of the system.

The controller 500 may control the simulator device 100, the hydraulic pressure supply device 200, the hydraulic control device 300, and the cut valve 400.

Hereinafter, the braking control operation of the electronic brake system equipped with the above-described components will be described.

When the driver manipulates the brake pedal 10, the control unit 500 may turn off the first cut valve 410 and the second cut valve 420 to close the brake pedal 10. The flow path between the master cylinder 20 and the hydraulic control device 300 may be closed. The hydraulic pressure discharged from the master cylinder 20 may not be transmitted to each wheel cylinder 40.

In addition, the controller 500 may operate the hydraulic pressure supply device 200. The controller 500 may turn on and open the first control valve 231 and the second control valve 232 and operate the motor 221 of the motor actuator 220. A hydraulic pressure may be generated in the first pressure chamber 212 by moving the hydraulic piston 214 by the operation of the motor 221. The hydraulic pressure discharged from the first pressure chamber 212 is controlled from the first hydraulic circuit 310 of the hydraulic control device 300 through the first control valve 231 and the second control valve 232 converted to an open state. 2 It can be delivered to the hydraulic circuit (320). The hydraulic pressure delivered to the first hydraulic circuit 310 and the second hydraulic circuit 320 is transmitted to each wheel cylinder 40 through the first inlet valve to the fourth inlet valve 311, 312, 321, and 322. It can generate braking force on the wheel.

In addition, when it is necessary to increase the hydraulic pressure discharged from the hydraulic pressure supply device 200, the control unit 500 additionally turns on and opens the third control valve 233 and turns off the fourth control valve 234 to close it. I can make it. Accordingly, a part of the hydraulic pressure discharged from the first pressure chamber 212 is transferred to the second pressure chamber 213 and used to push the hydraulic piston 214, thereby discharging the hydraulic pressure from the first pressure chamber 212. Can increase.

The control unit 500 operates the anti-lock braking system (ABS), traction control system (TCS) operation, or electronic stability control (ESC) operation, among the above braking controls. When it is necessary to perform various braking operations that can generate different braking forces for each, the first to fourth inlet valves 311, 312, 321, of the first hydraulic circuit 310 and the second hydraulic circuit 320 322) and the first to fourth outlet valves 313, 314, 323, and 324 are turned on or off to close or open, or the first hydraulic circuit 310 using a Pulse Width Modulation (PWM) control. ) And the opening degrees of the first to fourth inlet valves 311, 312, 321, 322 and the first to fourth outlet valves 313, 314, 323, 324 of the second hydraulic circuit 320 The hydraulic pressure of each wheel cylinder 40 can be increased, maintained or decreased.

In this way, when controlling the braking of the electronic brake system, a braking force can be secured by turning on or off various solenoid valves.

As described above, in the electronic brake system, the operation of the solenoid valve may be restricted according to the voltage applied from the battery provided in the vehicle. That is, when the voltage of the battery momentarily drops during the operation of the electronic brake system, the current supplied to the operating solenoid valve decreases, so that the operating solenoid valve may not be turned on and turned off. For this reason, it is difficult to ensure the operation stability of the solenoid valve, and the pressurization or depressurization performance may deteriorate.

The electronic brake system according to an embodiment increases the current supplied to the solenoid valve in operation when the voltage of the battery momentarily drops during braking control, thereby ensuring the operation stability of the solenoid valve in operation even if the system voltage fluctuates. Can be secured stably.

2 shows a control block of an electronic brake system according to an embodiment.

Referring to FIG. 2, the electronic brake system may include a control unit 500 that performs overall control.

A pedal displacement sensor 11, a voltage sensor 600, a motor driving unit 700, and a valve driving unit 800 are electrically connected to the control unit 500.

The pedal displacement sensor 11 may detect the operation and displacement of the brake pedal 10.

The voltage sensor 600 may detect the voltage of a battery provided in the vehicle. The voltage sensor 600 may detect a voltage input to the electronic brake system from a battery provided in the vehicle. The voltage sensor 600 may detect a voltage input to the motor M of the electronic brake system 1000 from a battery provided in the vehicle.

The motor driving unit 700 may drive the motor 221 according to a motor driving signal from the control unit 500.

The valve driving unit 800 may drive various solenoid valves V of the electronic brake system according to a valve driving signal from the control unit 500. The controller 500 may output an on/off driving signal for turning on or off the solenoid valves V to the valve driving unit 800. The control unit 500 may output a duty control signal for adjusting the opening degree of the solenoid valves V to the valve driving unit 800.

As described above, various solenoid valves V of the electronic brake system may include solenoid type solenoid valves.

For example, in general, a solenoid type solenoid valve is a sleeve coupled to the outside of an armature, an armature installed in the sleeve and provided to move forward and backward, a plunger that rises and falls to open and close the orifice by the advancing and retreating motion of the armature, and plungers. An elastic member that presses the shaft toward the armature, a valve core that provides a plunger and an elastic member in the through hole and forms an inner space in the longitudinal direction, a valve seat provided in the inner space to form an orifice, and installed outside the sleeve to advance and retreat the armature Excitation coils may be included.

In the case of a normally open solenoid type solenoid valve, when current is supplied to the excitation coil, the armature advances toward the valve core by the magnetic force acting between the armature and the valve core, and the plunger advances toward the valve seat, closing the orifice. When no current is supplied to the excitation coil, the magnetic force is released, so the plunger is separated from the valve seat by the elasticity of the elastic member and the orifice is opened. As described above, the normally open solenoid type solenoid valve can control the supply of hydraulic pressure flowing through the flow path as the orifice is repeatedly closed or opened according to the plunger's advancing and retreating motion.

The controller 500 may include a processor 510 and a memory 132.

The processor 510 may drive various electromagnetic valves V of the electronic brake system through the valve driving unit 700 according to information sensed through the pedal displacement sensor 11 and the voltage sensor 600 and the braking mode. .

The processor 510 corrects the target current of the solenoid valve in operation among various solenoid valves of the electronic brake system 1000 according to the voltage of the battery provided in the vehicle, and causes the current of the solenoid valve in operation to reach the corrected target current. The solenoid valve can be controlled.

The processor 510 increases the current supplied to the operating solenoid valve during the momentary voltage drop of the battery provided in the vehicle during braking control to the maximum current ensuring cut-in within the pressure band guaranteed by the operating solenoid valve. By doing so, even if the battery voltage of the vehicle drops momentarily, the operation stability of the solenoid valve can be ensured, thereby securing braking performance.

The memory 520 includes a cut-in current value, a cut-out current value, a max current value, and a cut-in current value of the various solenoid valves V of the electronic brake system 1000. A hold current value, a maintain current value, and the like may be stored in advance.

The memory 520 includes not only volatile memories such as S-RAM and D-RAM, but also flash memory, read-only memory (ROM), and Erasable Programmable Read Only Memory (EPROM). It may include non-volatile memory.

3 shows a target current pattern of the solenoid valve in the electronic brake system according to an embodiment.

Referring to FIG. 3, the solenoid valve of the electromagnetic brake system 1000 is a cut-in current value, a cut-out current value, a max current value, and a hold value for each valve type. The current (hold current) value and the maintain current (maintain current) value are set in advance.

The cut-in current is a current for actually operating the solenoid valve and may be a critical current for turning on the solenoid valve in an off state.

The cut-out current is a current for actually releasing the solenoid valve, and may be a critical current at which an on-state solenoid valve is turned off.

The max current may be a maximum current that guarantees cut-in within a pressure band guaranteed by the solenoid valve when turning on the solenoid valve during braking control. The max current may have a current value higher than the cut-in current by a preset current value.

The hold current may be a holding current for maintaining the ON state of the solenoid valve in operation during braking control. The hold current may have a current value higher than the cutout current value and lower than the max current value.

The maintain current may be a minimum holding current for deferring the operation of the solenoid valve during non-braking. The maintain current may have a current value higher than the cut-out current value in non-braking and lower than the cut-in current value.

The solenoid valve can be turned on if the current supplied to the excitation coil is more than the cut-in current, and can be turned off if the cut-out current falls. The turned on solenoid valve can be kept on if the current supplied to the excitation coil maintains the hold current.

In the electromagnetic brake system, in order to turn on the solenoid valve during braking control where hydraulic pressure is applied to both ends of the solenoid valve, first start supplying current to the excitation coil of the solenoid valve and increase the supplied current value until it reaches the max current value. have. When the max current value is reached, the max current value can be maintained for a preset time and then reduced to the hold current value. Accordingly, the solenoid valve may be switched from the off state to the on state and then maintain the on state.

4 is a diagram illustrating changing a target current of the solenoid valve upon an instantaneous voltage drop during braking control of the electronic brake system according to an exemplary embodiment.

Referring to FIG. 4, if an instantaneous voltage drop occurs in the battery while the solenoid valve in operation maintains the hold current during braking control of the electronic brake system, the solenoid valve in operation fails to maintain the hold current and falls below the cutout current. It may not be possible to keep the solenoid valve on.

If an instantaneous voltage drop occurs in the battery while the solenoid valve in operation during braking control maintains the hold current, the processor 510 corrects the target current value of the solenoid valve in operation to a max current value higher than the hold current value, and operates. The current of the running solenoid valve can be controlled so that the current value of the running solenoid valve reaches the max current value. That is, when the instantaneous voltage drop occurs at the time point t1, the current of the solenoid valve can be increased from the hold current value to the max current value.

Therefore, if an instantaneous voltage drop occurs during the braking control of the electronic brake system, it is possible to prevent the operating solenoid valve from being turned off without maintaining the hold current, thereby preventing the deterioration of pressurization or depressurization performance due to valve off, and valve operation. Stability can be guaranteed.

5 illustrates a change of a target current of the solenoid valve from a hold current to a max current and then back to a hold current when an instantaneous voltage drops during braking control of the electronic brake system according to an exemplary embodiment.

5, when the current value of the solenoid valve in operation reaches the max current value, the processor 510 determines the state in which the current value of the solenoid valve in operation reaches the max current value for a preset time. After holding for a while, the current value of the solenoid valve in operation can be reduced from the max current value to the hold current value again.

6 shows a control flow of an electronic brake system according to an embodiment.

Referring to FIG. 6, the processor 510 senses a voltage input to the electronic brake system 1000 from the battery of the vehicle through the voltage sensor 600 (1000 ). At this time, instead of directly sensing the voltage through the voltage sensor 600, the processor 510 may also receive from a system that recognizes voltage information of a vehicle battery among systems mounted on the vehicle through a vehicle network such as a CAN transceiver. It is possible.

The processor 510 determines whether an instantaneous voltage drop occurs according to a voltage input to the electronic brake system from the battery of the vehicle during braking control of the electronic brake system (1100). At this time, if the rate of change of the voltage is reduced by more than a preset rate of change, it may be determined that an instantaneous voltage drop has occurred.

If, as a result of determining the operation mode 1100, an instantaneous voltage drop occurs during the braking control of the electronic brake system, the processor 510 may change the target current of the solenoid valve in operation (1200). The processor 510 may change the target current of the solenoid valve maintaining the operating state from the hold current to the max current. At this time, the processor 510 is operated so that the operation of the solenoid valve in operation is not affected by the voltage decrease even when the voltage input to the electronic brake system from the vehicle battery is lower than the preset voltage during braking control of the electronic brake system. The target current of the valve can be changed.

The processor 510 changes the target current value of the solenoid valve in operation to a max current value higher than the hold current value, and then increases the current of the solenoid valve in operation so that the current value of the solenoid valve in operation reaches the changed max current value. Can (1300).

The processor 510 may determine whether the current value of the solenoid valve being operated reaches the max current value (1400).

If, as a result of determining the operation mode 1400, the current value of the solenoid valve in operation does not reach the max current value, the operation mode 1300 may be moved to perform the following operation modes.

Meanwhile, as a result of the determination of the operation mode 1400, when the current value of the solenoid valve in operation reaches the max current value, the processor 510 maintains the state in which the current value of the solenoid valve in operation reaches the max current value for a preset time. After that, the current value of the solenoid valve in operation is reduced from the max current value to the hold current value (1500). In this way, when an instantaneous voltage drop occurs during the braking control of the electronic brake system 1000, it is possible to prevent the solenoid valve in operation from being turned off without maintaining the hold current, thereby preventing deterioration in braking performance, and operation of the valve. Stability can be guaranteed.

In the above-described embodiment, it is described that the electronic brake system is an integrated electronic brake system that generates braking pressure by directly driving a pressure piston with a motor, but the present invention is not limited thereto. It may be an active electronically controlled brake system (ACTIVE HYDRAULIC BOOSTER SYSTEM; AHB system) consisting of a high-pressure device and an integrated ABS/ESC brake actuation device. In addition, the electronic brake system may be a variety of electronic brake systems using solenoid valves such as ABS, TCS, or ESC.

10: brake pedal 20: master cylinder
30: reservoir 40: wheel cylinder
100: simulation device 110: pedal simulator
120: simulator valve 200: hydraulic pressure supply device
210: hydraulic supply unit 220: motor actuator
230: a plurality of control valves 300: hydraulic control device
400: cut valve

Claims (10)

In the electronic brake system having a hydraulic circuit supplying hydraulic pressure to a wheel cylinder,
A plurality of solenoid valves provided to open and close the flow path of the hydraulic circuit; And
During braking control, the solenoid valve corrects the target current of the solenoid valve in operation among the plurality of solenoid valves based on the voltage input from the battery of the vehicle, and the solenoid valve so that the current of the solenoid valve in operation reaches the corrected target current Electronic brake system comprising a control unit for increasing the current supplied to the. The method of claim 1,
The control unit is an electronic brake system for correcting a target current of the operated solenoid valve when the instantaneous voltage of the battery drops. The method of claim 1,
The control unit increases the target current of the solenoid valve in operation to a maximum current that guarantees operability within a pressure band guaranteed by the solenoid valve in operation. The method of claim 3,
The control unit increases the current of the solenoid valve in operation to the max current, and when the max current is reached, the control unit maintains for a preset period of time and then decreases to a hold current for maintaining the ON state of the solenoid valve in operation. Brake system. The method of claim 1,
The control unit increases a target current of an operating solenoid valve among the plurality of solenoid valves when a voltage input from the battery is lower than a preset voltage. The method of claim 1,
Electronic brake system comprising a voltage sensor for sensing the voltage input from the battery. In the control method of an electronic brake system having a hydraulic circuit supplying hydraulic pressure to a wheel cylinder,
During braking control, the voltage input from the vehicle's battery is sensed,
Based on the sensed voltage, a target current of a solenoid valve in operation among a plurality of solenoid valves for opening and closing the flow path of the hydraulic circuit is corrected,
A control method of an electronic brake system for increasing the current of the operating solenoid valve so that the current of the operating solenoid valve reaches the corrected target current. The method of claim 7,
In the correction of the target current, when a voltage input from the battery is lower than a preset voltage, a target current of an operating solenoid valve among the plurality of solenoid valves is increased. The method of claim 8,
The increase in the current of the solenoid valve in operation increases the target current of the solenoid valve in operation to a maximum current that guarantees operability within a pressure band guaranteed by the solenoid valve in operation. The method of claim 9,
When the current of the operating solenoid valve reaches the max current, an electronic brake system that maintains the current of the operating solenoid valve for a preset time and then reduces to a hold current for maintaining the on state of the operating solenoid valve Control method.

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